Fire as undesired burning can cause huge damage to property but also kills or injure people and animals. In my bachelor thesis I focused on thermovision diagnostics and thermovision cameras as one of the possibilities of early detection of fire and protection of life and health. From the knowledge gained from the professional literature, I have described the basics of thermodiagnostic diagnostics, the possibility of contactless measurement of temperature and properties and the possibility of thermovision camera. Thermocamera as a facility for early detection of fire or injured persons in the established area helps inciting firefighters to increase the effectiveness of the interventions, to save the lives of people affected by fire and to protect the firefighters themselves.